Cooling towers should be cleaned and disinfected at least twice a year. Normally this maintenance will be performed before initial start-up at the beginning of the cooling season and after shutdown in the fall. These areas can sometimes become clogged with debris that is not removed from the system through normal filtration. All distribution pans should be opened and cleaned providing increased water flow. Reduction in flow from clogged distributors can reduce the tower ability to cool water tremendously. Left untreated, this can cause major increases in energy usage.